PROCEDURE FOR REPAIR OF IRON PARTS WITH CRACKS BY MECHANISED WELDING Russian patent published in 2010 - IPC B23P6/04 B23K25/00 B23K9/16 

FIELD: machine building.

SUBSTANCE: invention can be used at repair of large-size thick wall iron parts with complex deep and long crack in plane. There is bored a row of through orifices of specified diametre at a specified space along trajectory of the crack and perpendicular to surface of its development. The space between through orifices should facilitate overlap of a preceding seam with the following one at weld of each orifice. Diametre of orifices is chosen depending on degree of deviation of the crack from vertical. A removable process plug out of graphite is installed into each successive orifice; the plug eliminates overflow of melt from the preceding orifice into the following orivice through a bridge formed with a section of the crack between orifices. Depending of diametre of the orifice it is welded either by electric slag method or by arc welding with austenite high nickel wire under a mode of electric heating, thereby producing a solid seam. From beneath under orifices there is positioned a graphite crucible. Also there can be formed a bed by charging first dry sand, then iron chips or shot over sand through an orifice; charge is successively compacted to plug an output from the orifice. Crack zone is locally heated along whole cross section of the part.

EFFECT: procedure ensures raised strength of crack repair producing monolith, also reduces labour input of repair.

6 cl, 1 dwg